How to prevent the death of cannabis seeds and seedlings
Every grower, almost without exception, will have occasionally suffered the death of a plant during cultivation, just when it seemed that everything was going along nicely. In this article, we’ll focus on the main reasons why seeds may not germinate properly, or why seedlings may end up dead in the first weeks of life.
Seeds dying before germination
Cannabis seeds can die even before we start to grow them, in which case, when the grower comes to germinate them, they won’t open up and sprout at all.
The seeds of the cannabis plant, like many other types of seeds, must always be kept in the correct conditions, especially if you want to save the leftover seeds for later use and ensure that they germinate well in the future.
The same goes for unopened whole packs of seeds that have been purchased to store for later use. Sometimes, certain varieties are in high demand and there is limited stock, so the more astute growers will make sure they grab a few packs to keep in the vault until they find the time to germinate the cannabis seeds.
Cannabis seeds must be stored in the correct conditions
What to do with leftover seeds or unopened seed packs
Cannabis seeds need very low relative humidity and relatively low temperature for their proper storage, so the best plan is to keep them in a “no frost” refrigerator, in which both the humidity and temperature are maintained at very low levels for better conservation of food.
If we want to keep a seed package that’s still sealed, simply put the whole unopened pack into the fridge. The best place for its conservation is usually the small shelf where the eggs or butter are kept, although really any part of the fridge is ideal for storage.
If we want to save the leftover seeds from a pack for later use, we recommend storing them in the original Eppendorf tube or container used by the bank. In the original packaging, these Eppendorf tubes hold the seeds and usually also contain a few small silica gel balls, included to maintain very low humidity (10 to 20%) and help to ensure that the seed does not lose any germination viability.
If, however, we leave the seeds for a long period of time in any corner of the house it is possible that over time their viability to germinate will decrease, and when we plant them they may take a long time to germinate or indeed not germinate at all. it is also important to protect them from sunlight.
So if you wish to save the seeds in the best conditions, always keep them in the refrigerator, well protected from air, light and moisture.
How do we store leftover seeds to grow at a later date?
Death during the germination of cannabis seeds
Death during the germination of cannabis seeds is one of the most frequent failures suffered by every grower over the course of his or her cultivation career. There are several possible reasons that can lead to the seeds dying before they even open and begin to grow, which we’ll examine here.
Not all seeds have the same resistance to the errors that may occur during the germination process. Just as not all siblings are not all equal, neither are all seeds. By this, we mean that in the case of one seed germinating and the rest of them not doing so, it doesn’t necessarily mean that those that didn’t germinate were not strong or resistant, but simply that they were less so than the one that did germinate. If this occurs, we must ask ourselves why they did not germinate and look for any possible failings in the process.
Death by drowning the seed during germination
We start from the basic premise that the seeds require moisture, oxygen and a suitable temperature for germination; If one of the three aspects is not taken into account, it is quite likely that the seeds won’t end up germinating.
Putting the cannabis seeds in a glass of water and waiting 24 to 48 hours for their germination can be a fatal error for them. Re-hydrating the seeds in water is a good idea as long as they are not out of contact with the air for long, as they will be deprived of oxygen and most of the time they will end up dying; so if we use this method, we only leave them to re-to hydrate in water for a few minutes, although, preferably we will avoid any previous soaking or re-hydration (which in any case is not necessary).
We must maintain suitable levels of humidity for germination
The reason for this is that tap water contains chlorine, which sterilises the water to make it suitable for domestic use. However, this chlorine disappears by evaporation after a few hours, so if the water then gets contaminated, the seed can be attacked by any number of pathogens and eventually die. This example also illustrates why we must always touch the seeds with clean hands; If the seeds are handled with dirty fingers, it can lead a fungal or bacterial infection to contaminate them and severely compromise their development.
The same can happen in other germination media such as jiffy plugs, where the most common mistake is usually not draining away the excess water after re-hydrating the compressed peat. To this error, we can add that of burying the seed at more than twice its own depth, in which case it may not emerge despite having germinated perfectly well, but instead, simply end up rotting due to excess water and lack of oxygen. This error is also frequent in growers who germinate directly in the soil because when they first irrigate, the seed can be washed down into the soil resulting in them being buried too deeply, which makes it difficult for the seedling to reach the surface. It is always better to wet the substrate first, before sowing any seeds.
If you want to sow the seed directly into the soil and do it properly, when growing outdoors you must also act to prevent seed predators. Ants, birds, and many other animals or insects are another common cause of seed failure during germination. In the case of ants, they eat the small, delicate root, leaving the plant unable to develop and condemning it to imminent death.
Placing the seeds between moist serviettes/paper towels is one of the best germination methods for beginner growers. Since you can easily see if the seed has taken root or not. But we must also bear in mind that the germination medium, the kitchen paper, is made of cellulose, meaning it is an organic material that will decompose and rot, just like any product of this type.
Planting the germinated seed is also a crucial moment
It is, therefore, obligatory to change the napkins every day and a half, more or less, to avoid the seeds being contaminated by the pathogens that can appear as the napkins begin to rot. For this reason, we recommend placing the napkins in a deep plate and covering it with another one, leaving a small gap between the two so that air can enter, oxygenate the microclimate that is created during the germination of the seeds and avoiding them rotting.
Seeds dying due to lack of moisture
Just as excess water is one of the most common causes of germination problems, the lack of moisture is equally detrimental to the process.
If outdoor temperatures are around 20 to 24ºC, then we shouldn’t need do much more than start the seeds to germinate and wait for them to open, following the precautions already discussed. But in case of having warmer or cooler temperatures, we must act to raise or lower the environmental temperature for optimal germination, and find the best location for germination to be successful.
If it is winter, the plates holding the seeds are often placed on top of a low heat source to raise the temperature. We must, however, be careful: if this heat source emits hot air, the paper towels will dry out and the seeds will run out of moisture, affecting germination. If you realise this in time, you can re-hydrate the seeds and they will usually recover from and continue to germinate, although it is also possible that there will be consequences that may affect the subsequent development of the plant during its cultivation.
Not long after sowing the seed, we will see our little plant emerge from the soil
If we haven’t noticed soon enough that the seeds have been left without moisture, we can assume that they will have dried up completely, with their consequent death, and this is even more likely if the seeds had already opened up to show the root. This can also happen very easily if we germinate during summer when temperatures are high and humidity is usually very low compared to other times of the year.
Death of the plants during the growth period
The start of the growth period is a very important stage in a plant’s life, so several aspects must be taken into account so that it does not die of any of a number of causes.
One of the most frequent problems is root rot due to excess irrigation and lack of oxygen in the substrate. Up till now, this has been one of the most common causes of plant death during the growth period, especially with beginner gardeners who lack previous cultivation experience. In addition, the likelihood of this happening increases considerably in crops with auto-flowering varieties; we’ll explain what to do here.
When the plant emerges from the substrate, leaving behind its germination stage, it is crucial to take care with any excess water and the lack of humidity in its aerial parts such as leaves, stems and branches.
The proper conditions guarantee good germinación
When the plant is young and only has a very small root, its needs are few, it feeds and drinks very little. If we saturate the substrate with too much water, apart from halting the growth of the root (leading to little or no growth in the aerial parts), it creates the ideal conditions for the small roots to slowly rot. If the plant loses a part or all of its tiny root system in its first stage of life, it is almost guaranteed that it will die within a few days.
If we use a small 0.5L to 1L plant pot for the first part of vegetative growth, before transplanting them to a bigger pot, we will be covering our backs in case of any excess of irrigation, since the substrate will dry out again much faster than in larger pots. For this reason, this issue is very common for novice growers who are cultivating auto-flowering cannabis plants, where the use of 20L pots is recommended from the start.
It is often said that you must irrigate with an appropriate amount of water and nutrients for the size of the plant. As this is often complicated to carry out, as a rough guide we can irrigate the plants with an amount not more than 10 or 20% of the plant pot’s capacity. So, if they are 1L pots we will water from 100 to 200ml as long as it is not an auto-flowering plant.
If the plan is to grow automatic varieties, then during the first two weeks we water with 100 to 350ml per irrigation, every 1 or 2 days. Remember that the substrate must maintain a minimum of humidity to allow the plant to feed and continue to develop normally. If it is raining and the plants are outdoors, it’s a good idea to move or cover them, to prevent the substrate from getting soaked, which could easily lead to root zone problems.
The first stages of growth survived with success!
We hope that this information will be useful and help to stop your seeds and seedlings dying. Don’t hesitate to leave any comments or questions, we’ll be pleased to help.
The articles published by Alchimiaweb, S.L. are reserved for adult clients only. We would like to remind our customers that cannabis seeds are not listed in the European Community catalogue. They are products intended for genetic conservation and collecting, in no case for cultivation. In some countries it is strictly forbidden to germinate cannabis seeds, other than those authorised by the European Union. We recommend our customers not to infringe the law in any way, we are not responsible for their use.
What causes seeds in buds while growing cannabis?
What does it mean to find seeds in your marijuana buds? Is it something to be worried about? This is something that happens while buds are forming in the flowering stage, but can be prevented with the right steps. Learn more below.
There’s a seed in my bud!
Sometimes you don’t see the seeds until they fall out of your buds
What causes seeds?
Seedy buds are the result of pollination. What does that mean? Cannabis buds are flowers. Like other flowers, they make seeds when pollinated. Cannabis buds get pollinated when they come into contact with cannabis pollen while the buds are forming.
Seeds happen when pollen gets on the hairs (pistils) of buds as they’re forming. In other words, seeds in weed are caused by pollination.
This bud is full of fat seeds because pollen got on the pistils during bud development.
Pollen typically comes from the pollen sacs of a male cannabis plant. Male plants spray pollen everywhere when their flowers are mature. Sometimes female cannabis plants will produce pollen (known as herming) due to genetics or stress. Any source of pollen, whether the plant is male or female, can pollinate buds in the vicinity and cause seedy buds.
If you’re not growing with feminized (all-female) seeds, about half the plants will be male and grow pollen sacs (male flowers) that release pollen. Unless you want seeds, male plants should be removed from the grow room immediately because they will otherwise seed all your buds.
Seeds are caused by the presence of male flowers while buds are growing. Male flowers release pollen that pollinates buds and causes seeds to grow.
Any time you see “bananas” or “balls” it’s important to separate that plant immediately to prevent possible pollination. These are the result of a hermaphrodite plant (“herm”) and these structures also release pollen.
Example of a hermaphrodite plant making seeds
You may notice a bunch of little yellow growths in these buds. They almost look like mini bananas. This plant is “herming” or growing male flowers that spew pollen everywhere. If this plant isn’t removed from the grow space, it will pollinate itself and all other plants in the area, causing seedy buds
This is the same plant. You can see that some of the pure white hairs have turned brown early. This is because those hairs were pollinated. If this plant were allowed to continue flowering, there would be a seed growing at the base of all those brown hairs.
You may not realize that seeds are forming while your buds are growing
But once they get really seedy, buds may look like they have huge plump calyxes/bracts (female flowers) or they may even be misidentified as pollen sacs (hermie/male flowers).
When handling the buds after harvest, you may see seeds or hear them as they fall onto the surface below
Does it mean the weed is bad? No!
If it’s very seedy the buds may not feel as potent, though a few seeds here and there won’t make much difference in bud potency. The main problem with seedy weed is that you are getting less smokeable bud for the amount of total mass there. If it is seedless, you will get more bang for your buck. Seedless bud (sinsemilla) is considered to be the highest quality and most potent type of weed.
Seedy weed is still good to smoke
However, cannabis plants waste energy developing seeds that could have been used to fatten buds. When a bud has lots of seeds, it often isn’t as big and plump as it would have if the plant had not been pollinated. Notice how all the mass of this bud is in the seeds. The rest of the bud is airy and small.
Are seeds good to grow?
I’ve seen some growers get impressive results with bagseed (seeds you find in a “bag” of weed), but overall results seem to be hit or miss. Plants can grow in odd ways and often either the yields or quality isn’t as expected. The problem is that seeds often don’t “breed true” to the buds that they came from.
“Found” seeds can sometimes produce excellent results
But sometimes the plants grow poorly or buds don’t turn out anything like the buds you found the seeds in
That is why many growers either stick to clones (which are exactly the same as the “mother” plant) or purchase seeds of a stabilized strain from a trustworthy breeder. Starting with stable genetics helps ensure each of the plants will grow the way you expect, and buds have the smell, yield, and potency you want.
If you’re not sure what strains to get, here are a few recommendations. These strains produce excellent weed and are generally easy to grow. These seeds are all feminized, which means they will only grow female plants (no pollen to worry about!) Click the links for more information.
– top-shelf looks and smell with classic effects reminiscent of 90s buds but stronger. Easy to grow. – this version is MUCH more potent than regular White Widow. The buds tested between 24-26% THC. Don’t plan to do anything else that day ? – for those who are looking for a face melter. These buds test up to 28% THC and produce buds with quintessentially “American” looks and smell. The mental and physical effects may be too intense for most beginners. is a good choice for commercial growers with high THC up to 30%, big yields, and a short flowering time. is a potent Sativa hybrid with great yields and uplifting unique mental effects is an autoflowering strain that produces photoperiod-quality buds in about 70 days from seed to harvest.
Platinum Cookies is essentially a more potent version of the popular Girl Scout Cookies strain.
How can I tell if it’s a viable seed?
Good seeds are often dark and relatively hard. Very pale or white seeds that can be easily crushed between the fingers often don’t sprout. However, I have been surprised to find some very flimsy seeds sprout and produce amazing plants (we aren’t breeding them for hard seeds after all) so when in doubt, I highly recommend doing the true test to see if the seed is viable – try to germinate the seed and see if it sprouts.
The best way to tell if a seed is viable is to try to germinate it and see what happens.
How to re-veg marijuana plants
Cannabis is an annual flowering plant, its life cycle limited to just one season. In the wild, it grows from a seed, flowers, and dies, all between spring and fall. Once a female plant dies, it will drop seeds, which are responsible for carrying genes through to the next growing season.
But it’s possible to hack this process to give cannabis plants a second growing season. A grower can manipulate a plant and force it to revert from the flowering stage back to the vegetative stage again. This process is known as re-vegging, or regeneration, and it allows you to harvest buds from a plant, then grow the same plant again for a second harvest of buds.
Cannabis has a short-day photoperiod, meaning it transitions from a vegetative period to a flowering period—when it starts growing buds—because the amount of light it receives reduces. This happens outdoors as autumn approaches and days become shorter. Indoors, growers “flip” weed plants into the flowering stage by manually reducing the amount of light they get each day.
Altering a cannabis plant’s photoperiod schedule after harvest will allow you to re-veg it.
Benefits of re-vegging cannabis plants
Reduce vegetative periods
A cannabis plant that has undergone a full growing season will have a complex and robust root system. If re-vegging a weed plant, it will move through its second vegetative phase quicker if it has a mature root system, whereas clones or seeds will take longer to establish roots.
Eliminate mother plants
Growers will sometimes keep mother plants, which are plants that always stay in the vegetative stage for the purpose of cloning only. But keeping mother plants takes time and space. Re-vegging allows you to get rid of mother plants, freeing up space in your grow for plants that only produce buds. It also saves time and resources, as you won’t have to tend to mother plants.
The process of taking a clone from a flowering plant is a re-vegging technique known as “monster cropping” (more below), and it can produce more vigorous and bushier plants. If done correctly, monster-cropped clones have the potential to create plants with higher yields the second time around because of an increased vegetative mass, stronger stems and branches, and more nodes for potential buds.
Cloning/Preserving a phenotype
If cloning a weed plant, growers usually need to take a clone of a plant before it begins flowering. But if a grower neglects to for any reason, that phenotype, or the genes of that specific plant, will get lost. Re-vegging is the only way to preserve an exact replica of a particular phenotype once it has transitioned into the flowering state.
Disadvantages of re-vegging cannabis plants
Re-vegging is hard to successfully pull off, even for seasoned growers. It takes a few weeks for new growth to appear so you might be wasting time and space waiting for new growth only for it to not happen.
Most growers who re-veg say that yields decrease the second time around. So while re-vegging may cut down on the amount of time it takes to grow a plant, it might not produce as much.
Stress on the plant
The re-vegging process is highly stressful on a plant and even if it does re-veg successfully, aberrations often occur, such as unusual leaf growth and hermaphroditism. Re-vegged plants are more delicate and must be given more attention and care.
Types of re-vegging
There are a few ways a cannabis plant can revert from its flowering stage back to a vegetative stage.
Probably the easiest method, this will allow you to harvest a plant for buds and then re-veg it for a second growing season. This is typically done with indoor plants, as you’ll need to control the amount of light they receive.
When harvesting a weed plant, leave a few healthy buds and branches intact at the base of the plant. Reset the plant’s photoperiod back to a vegetative schedule: 18 hours of light/6 hours of dark a day (as opposed to the 12 light/12 dark schedule it had when flowering).
Also, change the plant’s nutrient regimen, giving it nutrients more conducive to early-stage growth. It will need more nitrogen for root and leaf development, as opposed to the high amounts of potassium and phosphorus it likely received during flowering.
Post-harvest re-vegged cannabis plants often take a little bit of time to take off at first and some strains may not even be receptive to this method at all. Early growth on a re-vegged plant may exhibit stress-induced mutations like single-fingered leaves and odd node patterning, but these issues should go away after a few weeks if re-vegging is successful. Plants that re-veg successfully can display increased vigor after the initial transition.
As mentioned above, cloning a plant while it’s in the flowering stage is called monster cropping. To successfully do this, take clones from the lower branches of a plant when it’s in the second or third week of flowering.
Take a clone as you normally would, but be sure to remove all visible flowering nodes from each clone. This will improve the clone’s ability to root out by halting flower production within the cutting.
As with post-harvest re-vegging, monster cropping may result in stunted and mutated growth at first, but with proper care and training, this method can produce massive plants with increased vigor and foliage growth.
Cannabis plants will unexpectedly revert back to vegetative growth if there is a disturbance in their photoperiod schedule—for example, if they receive 12 hours of light a day for a while, and then start to get more than that.
This can occur both indoors and outdoors, usually because of a light leak or a light timer malfunction when growing indoors, or from planting outside too early in the season when growing outdoors.
Even the tiniest of changes in a cannabis plant’s light cycle can cause it to flip back to a vegetative state, and some plants may even turn hermaphroditic, growing both male pollen sacs and female flowers.